Now that China has become a global economic power, it's beginning to throw its weight around Asia as a military power as well. That's making China's neighbors — and the United States — nervous. And for good reason.
China and its neighbors disagree over who owns hundreds of islands in East Asia's seas – and, more important, vast offshore areas around those islands that could yield oil, gas or minerals.
In the South China Sea, parts of whose waters are claimed by many nations, a Chinese-built submersible set a record last summer by diving more than two miles to survey the seabed and to plant a Chinese flag on the bottom. China is building a big naval base on Hainan island, and Chinese patrol boats have seized Vietnamese fishing boats and detained their crews for fishing in disputed waters.
In the East China Sea, China and Japan have clashed over the uninhabited, Japanese-held Senkaku islands (China calls them the Diaoyu islands) and over each country's naval movements through the Miyako Strait.
And in the Yellow Sea to the north, China objected vociferously to planned U.S.-South Korean naval maneuvers, leading the United States to postpone the operation while insisting that it would occur at a later date.
The whole situation has Washington alarmed. "[China's] military capacity has been growing by and large unabated," Adm. Robert F. Willard, commander of U.S. forces in the Pacific, told Congress earlier this year, adding that some moves "appear designed to challenge our freedom of action in the region."
The Chinese say they're acting to regain sovereignty over islands and waters that they contend were once theirs, stolen by foreign powers when their country was weak. (Their neighbors dispute those claims.) China wants the United States, the distant power that has regulated Asia's balance of power since World War II, to butt out.
During a just-completed 10-day trip to China and the Pacific, I heard Chinese officials and scholars denounce the U.S. military presence in Asia with rhetoric that seemed resurrected from the Cold War.
I heard things like this: "We see the Obama administration forming close relationships with other countries against China," said Liu Guijin, an advisor to China's Ministry of Foreign Commerce. "I think it will be destabilizing."
Or this: "Suddenly, the United States is behaving aggressively toward China," complained Fan Gang, a leading Beijing economist and former government official.
And, in the middle of what increasingly sounds like Cold War-era saber-rattling — or, worse, the military rivalries of the late 19th century — smaller countries in East Asia are trying to figure out what it means for their future.
Some, like Vietnam and Singapore, have asked the United States to keep a big military force in Asia to counterbalance Chinese power. "America plays a role in Asia that China cannot replace," Singapore Prime Minister Lee Hsien Loong told the Wall Street Journal last week.
On Friday, President Obama met with Southeast Asian leaders at the United Nations, and aides said he would reaffirm the U.S. position opposing the use of force in the South China Sea.
Some China-watchers suggest that Beijing's new aggressiveness in the region is evidence that the Chinese military, which tends to be hawkish, has gained new influence over foreign policy. "The military has its own interests," a Chinese diplomat told me a bit undiplomatically. "The greater the tensions, the bigger budget they get."
For now, China seems to be simply testing its neighbors — and the United States — to see what it can get away with at a time when the Obama administration has its hands full in Afghanistan. But that may turn out to be a counterproductive foreign policy. Because of China's truculence, U.S. relations with Japan, Korea and Vietnam have almost never been better.
There are signs that China is softening its stance, at least for the moment. Premier Wen Jiabao made a point of telling reporters before his meeting with Obama on Wednesday: "Our common interests far outweigh our differences." And China has agreed to discuss restarting military-to-military contacts with the United States, which were suspended after the U.S. announced a $6.4-billion arms sale to Taiwan in January.
Over the long run, though, China's new assertiveness is likely to continue. The underlying causes —growing economic power, a gnawing need for oil and mineral resources, a history of well-founded grudges against foreign imperialists, a normal dose of old-fashioned nationalism — are still there.
And when the Chinese look at us (as they do) and see a diminishing economic power and a government that's going broke, they wonder how long we're going to pay for a big, expensive fleet patrolling off their coast.
The last time a new economic power rose in Asia and acquired great-power military clout, it was the 19th century and the new power was Japan. That story turned out badly — for Japan, China and everyone else.
Managing the impact of China's rise to great-power status — and with it, the loss of our own near-monopoly over military power in the Pacific — is one of the great challenges of U.S. statecraft in our time. How the process turns out could determine whether East Asia's 21st century is marked by peace or war.